org.apache.kafka.streams.state.Stores

public final class Stores extends Object

Factory for creating state stores in Kafka Streams.

When using the high-level DSL, i.e., StreamsBuilder, users create StoreSuppliers that can be further customized via Materialized. For example, a topic read as KTable can be materialized into an in-memory store with custom key/value serdes and caching disabled:


 StreamsBuilder builder = new StreamsBuilder();
 KeyValueBytesStoreSupplier storeSupplier = Stores.inMemoryKeyValueStore("queryable-store-name");
 KTable<Long,String> table = builder.table(
   "topicName",
   Materialized.<Long,String>as(storeSupplier)
               .withKeySerde(Serdes.Long())
               .withValueSerde(Serdes.String())
               .withCachingDisabled());

When using the Processor API, i.e., Topology, users create StoreBuilders that can be attached to Processors. For example, you can create a windowed RocksDB store with custom changelog topic configuration like:


 Topology topology = new Topology();
 topology.addProcessor("processorName", ...);

 Map<String,String> topicConfig = new HashMap<>();
 StoreBuilder<WindowStore<Integer, Long>> storeBuilder = Stores
   .windowStoreBuilder(
     Stores.persistentWindowStore("queryable-store-name", ...),
     Serdes.Integer(),
     Serdes.Long())
   .withLoggingEnabled(topicConfig);

 topology.addStateStore(storeBuilder, "processorName");

Constructor Summary

Constructors

Constructor

Description

Stores()
Method Summary

Modifier and Type

Method

Description

static KeyValueBytesStoreSupplier

inMemoryKeyValueStore(String name)

Create an in-memory KeyValueBytesStoreSupplier.

static SessionBytesStoreSupplier

inMemorySessionStore(String name, Duration retentionPeriod)

Create an in-memory SessionBytesStoreSupplier.

static WindowBytesStoreSupplier

inMemoryWindowStore(String name, Duration retentionPeriod, Duration windowSize, boolean retainDuplicates)

Create an in-memory WindowBytesStoreSupplier.

static <K, V> StoreBuilder<KeyValueStore<K,V>>

keyValueStoreBuilder(KeyValueBytesStoreSupplier supplier, Serde<K> keySerde, Serde<V> valueSerde)

Creates a StoreBuilder that can be used to build a KeyValueStore.

static KeyValueBytesStoreSupplier

lruMap(String name, int maxCacheSize)

Create a LRU Map KeyValueBytesStoreSupplier.

static KeyValueBytesStoreSupplier

persistentKeyValueStore(String name)

Create a persistent KeyValueBytesStoreSupplier.

static SessionBytesStoreSupplier

persistentSessionStore(String name, Duration retentionPeriod)

Create a persistent SessionBytesStoreSupplier.

static KeyValueBytesStoreSupplier

persistentTimestampedKeyValueStore(String name)

Create a persistent KeyValueBytesStoreSupplier.

static WindowBytesStoreSupplier

persistentTimestampedWindowStore(String name, Duration retentionPeriod, Duration windowSize, boolean retainDuplicates)

Create a persistent WindowBytesStoreSupplier.

static VersionedBytesStoreSupplier

persistentVersionedKeyValueStore(String name, Duration historyRetention)

Create a persistent versioned key-value store VersionedBytesStoreSupplier.

static VersionedBytesStoreSupplier

persistentVersionedKeyValueStore(String name, Duration historyRetention, Duration segmentInterval)

Create a persistent versioned key-value store VersionedBytesStoreSupplier.

static WindowBytesStoreSupplier

persistentWindowStore(String name, Duration retentionPeriod, Duration windowSize, boolean retainDuplicates)

Create a persistent WindowBytesStoreSupplier.

static <K, V> StoreBuilder<SessionStore<K,V>>

sessionStoreBuilder(SessionBytesStoreSupplier supplier, Serde<K> keySerde, Serde<V> valueSerde)

Creates a StoreBuilder that can be used to build a SessionStore.

static <K, V> StoreBuilder<TimestampedKeyValueStore<K,V>>

timestampedKeyValueStoreBuilder(KeyValueBytesStoreSupplier supplier, Serde<K> keySerde, Serde<V> valueSerde)

Creates a StoreBuilder that can be used to build a TimestampedKeyValueStore.

static <K, V> StoreBuilder<TimestampedWindowStore<K,V>>

timestampedWindowStoreBuilder(WindowBytesStoreSupplier supplier, Serde<K> keySerde, Serde<V> valueSerde)

Creates a StoreBuilder that can be used to build a TimestampedWindowStore.

static <K, V> StoreBuilder<VersionedKeyValueStore<K,V>>

versionedKeyValueStoreBuilder(VersionedBytesStoreSupplier supplier, Serde<K> keySerde, Serde<V> valueSerde)

Creates a StoreBuilder that can be used to build a VersionedKeyValueStore.

static <K, V> StoreBuilder<WindowStore<K,V>>

windowStoreBuilder(WindowBytesStoreSupplier supplier, Serde<K> keySerde, Serde<V> valueSerde)

Creates a StoreBuilder that can be used to build a WindowStore.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details
- Stores
  
  public Stores()
Method Details
- persistentKeyValueStore
  
  public static KeyValueBytesStoreSupplier persistentKeyValueStore(String name)
  
  Create a persistent KeyValueBytesStoreSupplier.
  This store supplier can be passed into a keyValueStoreBuilder(KeyValueBytesStoreSupplier, Serde, Serde). If you want to create a TimestampedKeyValueStore or VersionedKeyValueStore you should use persistentTimestampedKeyValueStore(String) or persistentVersionedKeyValueStore(String, Duration), respectively, to create a store supplier instead.
  
  Parameters:
  
  name - name of the store (cannot be null)
  
  Returns:
  
  an instance of a KeyValueBytesStoreSupplier that can be used to build a persistent key-value store
- persistentTimestampedKeyValueStore
  
  public static KeyValueBytesStoreSupplier persistentTimestampedKeyValueStore(String name)
  
  Create a persistent KeyValueBytesStoreSupplier.
  This store supplier can be passed into a timestampedKeyValueStoreBuilder(KeyValueBytesStoreSupplier, Serde, Serde). If you want to create a KeyValueStore or a VersionedKeyValueStore you should use persistentKeyValueStore(String) or persistentVersionedKeyValueStore(String, Duration), respectively, to create a store supplier instead.
  
  Parameters:
  
  name - name of the store (cannot be null)
  
  Returns:
  
  an instance of a KeyValueBytesStoreSupplier that can be used to build a persistent key-(timestamp/value) store
- persistentVersionedKeyValueStore
  
  public static VersionedBytesStoreSupplier persistentVersionedKeyValueStore(String name, Duration historyRetention)
  
  Create a persistent versioned key-value store VersionedBytesStoreSupplier.
  This store supplier can be passed into a versionedKeyValueStoreBuilder(VersionedBytesStoreSupplier, Serde, Serde).
  Note that it is not safe to change the value of historyRetention between application restarts without clearing local state from application instances, as this may cause incorrect values to be read from the state store if it impacts the underlying storage format.
  
  Parameters:
  
  name - name of the store (cannot be null)
  
  historyRetention - length of time that old record versions are available for query (cannot be negative). If a timestamp bound provided to VersionedKeyValueStore.get(Object, long) is older than this specified history retention, then the get operation will not return data. This parameter also determines the "grace period" after which out-of-order writes will no longer be accepted.
  
  Returns:
  
  an instance of VersionedBytesStoreSupplier
  
  Throws:
  
  IllegalArgumentException - if historyRetention can't be represented as long milliseconds
- persistentVersionedKeyValueStore
  
  public static VersionedBytesStoreSupplier persistentVersionedKeyValueStore(String name, Duration historyRetention, Duration segmentInterval)
  
  Create a persistent versioned key-value store VersionedBytesStoreSupplier.
  This store supplier can be passed into a versionedKeyValueStoreBuilder(VersionedBytesStoreSupplier, Serde, Serde).
  Note that it is not safe to change the value of segmentInterval between application restarts without clearing local state from application instances, as this may cause incorrect values to be read from the state store otherwise.
  
  Parameters:
  
  name - name of the store (cannot be null)
  
  historyRetention - length of time that old record versions are available for query (cannot be negative). If a timestamp bound provided to VersionedKeyValueStore.get(Object, long) is older than this specified history retention, then the get operation will not return data. This parameter also determines the "grace period" after which out-of-order writes will no longer be accepted.
  
  segmentInterval - size of segments for storing old record versions (must be positive). Old record versions for the same key in a single segment are stored (updated and accessed) together. The only impact of this parameter is performance. If segments are large and a workload results in many record versions for the same key being collected in a single segment, performance may degrade as a result. On the other hand, historical reads (which access older segments) and out-of-order writes may slow down if there are too many segments.
  
  Returns:
  
  an instance of VersionedBytesStoreSupplier
  
  Throws:
  
  IllegalArgumentException - if historyRetention or segmentInterval can't be represented as long milliseconds
- inMemoryKeyValueStore
  
  public static KeyValueBytesStoreSupplier inMemoryKeyValueStore(String name)
  
  Create an in-memory KeyValueBytesStoreSupplier.
  This store supplier can be passed into a keyValueStoreBuilder(KeyValueBytesStoreSupplier, Serde, Serde) or timestampedKeyValueStoreBuilder(KeyValueBytesStoreSupplier, Serde, Serde).
  
  Parameters:
  
  name - name of the store (cannot be null)
  
  Returns:
  
  an instance of a KeyValueBytesStoreSupplier than can be used to build an in-memory store
- lruMap
  
  public static KeyValueBytesStoreSupplier lruMap(String name, int maxCacheSize)
  
  Create a LRU Map KeyValueBytesStoreSupplier.
  This store supplier can be passed into a keyValueStoreBuilder(KeyValueBytesStoreSupplier, Serde, Serde) or timestampedKeyValueStoreBuilder(KeyValueBytesStoreSupplier, Serde, Serde).
  
  Parameters:
  
  name - name of the store (cannot be null)
  
  maxCacheSize - maximum number of items in the LRU (cannot be negative)
  
  Returns:
  
  an instance of a KeyValueBytesStoreSupplier that can be used to build an LRU Map based store
  
  Throws:
  
  IllegalArgumentException - if maxCacheSize is negative
- persistentWindowStore
  
  public static WindowBytesStoreSupplier persistentWindowStore(String name, Duration retentionPeriod, Duration windowSize, boolean retainDuplicates) throws IllegalArgumentException
  
  Create a persistent WindowBytesStoreSupplier.
  This store supplier can be passed into a windowStoreBuilder(WindowBytesStoreSupplier, Serde, Serde). If you want to create a TimestampedWindowStore you should use persistentTimestampedWindowStore(String, Duration, Duration, boolean) to create a store supplier instead.
  Note that it is not safe to change the value of retentionPeriod between application restarts without clearing local state from application instances, as this may cause incorrect values to be read from the state store if it impacts the underlying storage format.
  
  Parameters:
  
  name - name of the store (cannot be null)
  
  retentionPeriod - length of time to retain data in the store (cannot be negative) (note that the retention period must be at least long enough to contain the windowed data's entire life cycle, from window-start through window-end, and for the entire grace period)
  
  windowSize - size of the windows (cannot be negative)
  
  retainDuplicates - whether or not to retain duplicates. Turning this on will automatically disable caching and means that null values will be ignored.
  
  Returns:
  
  an instance of WindowBytesStoreSupplier
  
  Throws:
  
  IllegalArgumentException - if retentionPeriod or windowSize can't be represented as long milliseconds
  
  IllegalArgumentException - if retentionPeriod is smaller than windowSize
- persistentTimestampedWindowStore
  
  public static WindowBytesStoreSupplier persistentTimestampedWindowStore(String name, Duration retentionPeriod, Duration windowSize, boolean retainDuplicates) throws IllegalArgumentException
  
  Create a persistent WindowBytesStoreSupplier.
  This store supplier can be passed into a timestampedWindowStoreBuilder(WindowBytesStoreSupplier, Serde, Serde). If you want to create a WindowStore you should use persistentWindowStore(String, Duration, Duration, boolean) to create a store supplier instead.
  Note that it is not safe to change the value of retentionPeriod between application restarts without clearing local state from application instances, as this may cause incorrect values to be read from the state store if it impacts the underlying storage format.
  
  Parameters:
  
  name - name of the store (cannot be null)
  
  retentionPeriod - length of time to retain data in the store (cannot be negative) (note that the retention period must be at least long enough to contain the windowed data's entire life cycle, from window-start through window-end, and for the entire grace period)
  
  windowSize - size of the windows (cannot be negative)
  
  retainDuplicates - whether or not to retain duplicates. Turning this on will automatically disable caching and means that null values will be ignored.
  
  Returns:
  
  an instance of WindowBytesStoreSupplier
  
  Throws:
  
  IllegalArgumentException - if retentionPeriod or windowSize can't be represented as long milliseconds
  
  IllegalArgumentException - if retentionPeriod is smaller than windowSize
- inMemoryWindowStore
  
  public static WindowBytesStoreSupplier inMemoryWindowStore(String name, Duration retentionPeriod, Duration windowSize, boolean retainDuplicates) throws IllegalArgumentException
  
  Create an in-memory WindowBytesStoreSupplier.
  This store supplier can be passed into a windowStoreBuilder(WindowBytesStoreSupplier, Serde, Serde) or timestampedWindowStoreBuilder(WindowBytesStoreSupplier, Serde, Serde).
  
  Parameters:
  
  name - name of the store (cannot be null)
  
  retentionPeriod - length of time to retain data in the store (cannot be negative) Note that the retention period must be at least long enough to contain the windowed data's entire life cycle, from window-start through window-end, and for the entire grace period.
  
  windowSize - size of the windows (cannot be negative)
  
  retainDuplicates - whether or not to retain duplicates. Turning this on will automatically disable caching and means that null values will be ignored.
  
  Returns:
  
  an instance of WindowBytesStoreSupplier
  
  Throws:
  
  IllegalArgumentException - if retentionPeriod or windowSize can't be represented as long milliseconds
  
  IllegalArgumentException - if retentionPeriod is smaller than windowSize
- persistentSessionStore
  
  public static SessionBytesStoreSupplier persistentSessionStore(String name, Duration retentionPeriod)
  
  Create a persistent SessionBytesStoreSupplier.
  Note that it is not safe to change the value of retentionPeriod between application restarts without clearing local state from application instances, as this may cause incorrect values to be read from the state store if it impacts the underlying storage format.
  
  Parameters:
  
  name - name of the store (cannot be null)
  
  retentionPeriod - length of time to retain data in the store (cannot be negative) (note that the retention period must be at least as long enough to contain the inactivity gap of the session and the entire grace period.)
  
  Returns:
  
  an instance of a SessionBytesStoreSupplier
- inMemorySessionStore
  
  public static SessionBytesStoreSupplier inMemorySessionStore(String name, Duration retentionPeriod)
  
  Create an in-memory SessionBytesStoreSupplier.
  
  Parameters:
  
  name - name of the store (cannot be null)
  
  retentionPeriod - length of time to retain data in the store (cannot be negative) (note that the retention period must be at least as long enough to contain the inactivity gap of the session and the entire grace period.)
  
  Returns:
  
  an instance of a SessionBytesStoreSupplier
- keyValueStoreBuilder
  
  public static <K, V> StoreBuilder<KeyValueStore<K,V>> keyValueStoreBuilder(KeyValueBytesStoreSupplier supplier, Serde<K> keySerde, Serde<V> valueSerde)
  
  Creates a StoreBuilder that can be used to build a KeyValueStore.
  The provided supplier should not be a supplier for TimestampedKeyValueStores.
  
  Type Parameters:
  
  K - key type
  
  V - value type
  
  Parameters:
  
  supplier - a KeyValueBytesStoreSupplier (cannot be null)
  
  keySerde - the key serde to use
  
  valueSerde - the value serde to use; if the serialized bytes is null for put operations, it is treated as delete
  
  Returns:
  
  an instance of a StoreBuilder that can build a KeyValueStore
- timestampedKeyValueStoreBuilder
  
  public static <K, V> StoreBuilder<TimestampedKeyValueStore<K,V>> timestampedKeyValueStoreBuilder(KeyValueBytesStoreSupplier supplier, Serde<K> keySerde, Serde<V> valueSerde)
  
  Creates a StoreBuilder that can be used to build a TimestampedKeyValueStore.
  The provided supplier should not be a supplier for KeyValueStores. For this case, passed in timestamps will be dropped and not stored in the key-value-store. On read, no valid timestamp but a dummy timestamp will be returned.
  
  Type Parameters:
  
  K - key type
  
  V - value type
  
  Parameters:
  
  supplier - a KeyValueBytesStoreSupplier (cannot be null)
  
  keySerde - the key serde to use
  
  valueSerde - the value serde to use; if the serialized bytes is null for put operations, it is treated as delete
  
  Returns:
  
  an instance of a StoreBuilder that can build a KeyValueStore
- versionedKeyValueStoreBuilder
  
  public static <K, V> StoreBuilder<VersionedKeyValueStore<K,V>> versionedKeyValueStoreBuilder(VersionedBytesStoreSupplier supplier, Serde<K> keySerde, Serde<V> valueSerde)
  
  Creates a StoreBuilder that can be used to build a VersionedKeyValueStore.
  
  Type Parameters:
  
  K - key type
  
  V - value type
  
  Parameters:
  
  supplier - a VersionedBytesStoreSupplier (cannot be null)
  
  keySerde - the key serde to use
  
  valueSerde - the value serde to use; if the serialized bytes is null for put operations, it is treated as a deletion
  
  Returns:
  
  an instance of a StoreBuilder that can build a VersionedKeyValueStore
- windowStoreBuilder
  
  public static <K, V> StoreBuilder<WindowStore<K,V>> windowStoreBuilder(WindowBytesStoreSupplier supplier, Serde<K> keySerde, Serde<V> valueSerde)
  
  Creates a StoreBuilder that can be used to build a WindowStore.
  The provided supplier should not be a supplier for TimestampedWindowStores.
  
  Type Parameters:
  
  K - key type
  
  V - value type
  
  Parameters:
  
  supplier - a WindowBytesStoreSupplier (cannot be null)
  
  keySerde - the key serde to use
  
  valueSerde - the value serde to use; if the serialized bytes is null for put operations, it is treated as delete
  
  Returns:
  
  an instance of StoreBuilder than can build a WindowStore
- timestampedWindowStoreBuilder
  
  public static <K, V> StoreBuilder<TimestampedWindowStore<K,V>> timestampedWindowStoreBuilder(WindowBytesStoreSupplier supplier, Serde<K> keySerde, Serde<V> valueSerde)
  
  Creates a StoreBuilder that can be used to build a TimestampedWindowStore.
  The provided supplier should not be a supplier for WindowStores. For this case, passed in timestamps will be dropped and not stored in the window-store. On read, no valid timestamp but a dummy timestamp will be returned.
  
  Type Parameters:
  
  K - key type
  
  V - value type
  
  Parameters:
  
  supplier - a WindowBytesStoreSupplier (cannot be null)
  
  keySerde - the key serde to use
  
  valueSerde - the value serde to use; if the serialized bytes is null for put operations, it is treated as delete
  
  Returns:
  
  an instance of StoreBuilder that can build a TimestampedWindowStore
- sessionStoreBuilder
  
  public static <K, V> StoreBuilder<SessionStore<K,V>> sessionStoreBuilder(SessionBytesStoreSupplier supplier, Serde<K> keySerde, Serde<V> valueSerde)
  
  Creates a StoreBuilder that can be used to build a SessionStore.
  
  Type Parameters:
  
  K - key type
  
  V - value type
  
  Parameters:
  
  supplier - a SessionBytesStoreSupplier (cannot be null)
  
  keySerde - the key serde to use
  
  valueSerde - the value serde to use; if the serialized bytes is null for put operations, it is treated as delete
  
  Returns:
  
  an instance of StoreBuilder than can build a SessionStore

Class Stores

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Details

Stores

Method Details

persistentKeyValueStore

persistentTimestampedKeyValueStore

persistentVersionedKeyValueStore

persistentVersionedKeyValueStore

inMemoryKeyValueStore

lruMap

persistentWindowStore

persistentTimestampedWindowStore

inMemoryWindowStore

persistentSessionStore

inMemorySessionStore

keyValueStoreBuilder

timestampedKeyValueStoreBuilder

versionedKeyValueStoreBuilder

windowStoreBuilder

timestampedWindowStoreBuilder

sessionStoreBuilder